46 results on '"Dai Kuang"'
Search Results
2. Mobilizable plasmids drive the spread of antimicrobial resistance genes and virulence genes in Klebsiella pneumoniae
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Jianfeng Zhang, Yanping Xu, Meng Wang, Xiaobin Li, Zhiyuan Liu, Dai Kuang, Zixin Deng, Hong-Yu Ou, and Jieming Qu
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Mobilizable plasmid ,Antimicrobial resistance gene ,Virulence gene ,CRISPR–Cas system ,Klebsiella pneumoniae ,Medicine ,Genetics ,QH426-470 - Abstract
Abstract Background Klebsiella pneumoniae is a notorious clinical pathogen and frequently carries various plasmids, which are the main carriers of antimicrobial resistance and virulence genes. In comparison to self-transmissible conjugative plasmids, mobilizable plasmids have received much less attention due to their defects in conjugative elements. However, the contribution of mobilizable plasmids to the horizontal transfer of antimicrobial resistance genes and virulence genes of K. pneumoniae remains unclear. In this study, the transfer, stability, and cargo genes of the mobilizable plasmids of K. pneumoniae were examined via genetic experiments and genomic analysis. Methods Carbapenem-resistant (CR) plasmid pHSKP2 and multidrug-resistant (MDR) plasmid pHSKP3 of K. pneumoniae HS11286, virulence plasmid pRJF293 of K. pneumoniae RJF293 were employed in conjugation assays to assess the transfer ability of mobilizable plasmids. Mimic mobilizable plasmids and genetically modified plasmids were constructed to confirm the cotransfer models. The plasmid morphology was evaluated through XbaI and S1 nuclease pulsed-field gel electrophoresis and/or complete genome sequencing. Mobilizable plasmid stability in transconjugants was analyzed via serial passage culture. In addition, in silico genome analysis of 3923 plasmids of 1194 completely sequenced K. pneumoniae was performed to investigate the distribution of the conjugative elements, the cargo genes, and the targets of the CRISPR-Cas system. The mobilizable MDR plasmid and virulence plasmid of K. pneumoniae were investigated, which carry oriT but lack other conjugative elements. Results Our results showed that mobilizable MDR and virulence plasmids carrying oriT but lacking the relaxase gene were able to cotransfer with a helper conjugative CR plasmid across various Klebsiella and Escherichia coli strains. The transfer and stability of mobilizable plasmids rather than conjugative plasmids were not interfered with by the CRISPR–Cas system of recipient strains. According to the in silico analysis, the mobilizable plasmids carry about twenty percent of acquired antimicrobial resistance genes and more than seventy-five percent of virulence genes in K. pneumoniae. Conclusions Our work observed that a mobilizable MDR or virulence plasmid that carries oriT but lacks the relaxase genes transferred with the helper CR conjugative plasmid and mobilizable plasmids escaped from CRISPR–Cas defence and remained stable in recipients. These results highlight the threats of mobilizable plasmids as vital vehicles in the dissemination of antibiotic resistance and virulence genes in K. pneumoniae.
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- 2023
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3. Geography shapes the genomics and antimicrobial resistance of Salmonella enterica Serovar Enteritidis isolated from humans
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Guojie Cao, Shaohua Zhao, Dai Kuang, Chih-Hao Hsu, Lanlan Yin, Yan Luo, Zhao Chen, Xuebin Xu, Errol Strain, Patrick McDermott, Marc Allard, Eric Brown, Jianghong Meng, and Jie Zheng
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Medicine ,Science - Abstract
Abstract Multidrug-resistant (MDR) Salmonella has been a long-standing challenge in public health and food safety. The prevalence of MDR S. Enteritidis, especially isolated from humans, in China is significantly higher than those from the U.S. and other countries. A dataset of 197 S. Enteritidis genomes, including 16 sequenced clinical isolates from China and 181 downloaded genomes of human isolates from the U.S., Europe, and Africa, was analyzed for genomic diversity, virulence potential, and antimicrobial resistance (AMR). Phylogenomic analyses identified four major well-supported clades (I–IV). While AMR genotype in the majority of isolates in clades I and IV displayed as pan-susceptible, 81.8% (9/11) and 22.4% (13/58) of isolates in clades III and II were MDR, respectively. It is noted that 77% (10/13) of MDR isolates in clade II were from China. The most common antimicrobial resistance genes (ARGs) carried by the Chinese isolates were aph(3′)-IIa, bla CTX-M-55, and bla TEM-1B, whereas bla TEM-1B, sul1, sul2, drfA7, aph(3")-Ib/strA, and aph(6)-Id/strB were most often identified in those from Africa (clade III). Among the 14 plasmid types identified, IncX1 and IncFII(pHN7A8) were found exclusively in the Chinese MDR isolates, while IncQ1 was highly associated with the African MDR isolates. The spvRABCD virulence operon was present in 94.9% (187/197) of isolates tested and was highly associated with both the IncF (IncFII and IncFIB) plasmids. In addition, phylogenetic differences in distribution of Salmonella pathogenicity islands (SPIs), prophages and other accessory genes were also noted. Taken together, these findings provide new insights into the molecular mechanisms underpinning diversification of MDR S. Enteritidis.
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- 2023
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4. Development of Loop-Mediated Isothermal Amplification Rapid Diagnostic Assays for the Detection of Klebsiella pneumoniae and Carbapenemase Genes in Clinical Samples
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Aurore C. Poirier, Dai Kuang, Bianca S. Siedler, Khushboo Borah, Jai W. Mehat, Jialin Liu, Cui Tai, Xiaoli Wang, Arnoud H. M. van Vliet, Wei Ma, David R. Jenkins, John Clark, Roberto M. La Ragione, Jieming Qu, and Johnjoe McFadden
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rapid diagnostics ,antimicrobial resistance (AMR) ,Klebsiella pneumoniae (K. pneumoniae) ,carbapenemases genes ,LAMP (loop mediated isothermal amplification) ,Biology (General) ,QH301-705.5 - Abstract
Klebsiella pneumoniae is an important pathogenic bacterium commonly associated with human healthcare and community-acquired infections. In recent years, K. pneumoniae has become a significant threat to global public and veterinary health, because of its high rates of antimicrobial resistance (AMR). Early diagnosis of K. pneumoniae infection and detection of any associated AMR would help to accelerate directed therapy and reduce the risk of the emergence of multidrug-resistant isolates. In this study, we identified three target genes (yhaI, epsL, and xcpW) common to K. pneumoniae isolates from both China and Europe and designed loop-mediated isothermal amplification (LAMP) assays for the detection of K. pneumoniae in clinical samples. We also designed LAMP assays for the detection of five AMR genes commonly associated with K. pneumoniae. The LAMP assays were validated on a total of 319 type reference strains and clinical isolates of diverse genetic backgrounds, in addition to 40 clinical human sputum samples, and were shown to be reliable, highly specific, and sensitive. For the K. pneumoniae–specific LAMP assay, the calculated sensitivity, specificity, and positive and negative predictive values (comparison with culture and matrix-assisted laser desorption/ionization–time of flight mass spectrometry) were all 100% on clinical isolates and, respectively, of 100%, 91%, and 90%, and 100% when tested on clinical sputum samples, while being significantly faster than the reference methods. For the blaKPC and other carbapenemases’ LAMP assays, the concordance between the LAMP results and the references methods (susceptibility tests) was 100%, on both pure cultures (n = 125) and clinical samples (n = 18). In conclusion, we developed highly sensitive and specific LAMP assays for the clinical identification of K. pneumoniae and detection of carbapenem resistance.
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- 2022
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5. Characterization of internalin genes in Listeria monocytogenes from food and humans, and their association with the invasion of Caco-2 cells
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Xudong Su, Guojie Cao, Jianmin Zhang, Haijian Pan, Daofeng Zhang, Dai Kuang, Xiaowei Yang, Xuebin Xu, Xianming Shi, and Jianghong Meng
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L. monocytogenes ,Internalins ,inlA ,PMSC mutation ,Invasion ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Abstract Background Internalins are surface proteins that are utilized by Listeria monocytogenes to facilitate its invasion into human intestinal epithelial cells. The expression of a full-length InlA is one of essential virulence factors for L. monocytogenes to cross the intestinal barrier in order to invade epithelial cells. Results In this study, the gene sequences of inlA in 120 L. monocytogenes isolates from food (n = 107) and humans (n = 13) were analyzed. Premature stop codon (PMSC) mutations in inlA were identified in 51 isolates (50 from food and 1 from human). Six mutation types of PMSCs were identified. Among the 51 isolates with PMSCs in inlA, there were 44 serogroup 1/2c, 3c isolates from food, of which seven belonged to serogroups 1/2a, 3a. A total of 153,382 SNPs in 2247 core genes from 42 genomes were identified and used to construct a phylogenetic tree. Serotype 1/2c isolates with inlA PMSC mutations were grouped together. Cell culture studies on 21 isolates showed that the invasion to Caco-2 cells was significantly reduced among isolates with inlA PMSC mutations compared to those without PMSC mutations (P
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- 2019
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6. Genomic analyses of multidrug-resistant Salmonella Indiana, Typhimurium, and Enteritidis isolates using MinION and MiSeq sequencing technologies.
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Zhao Chen, Dai Kuang, Xuebin Xu, Narjol González-Escalona, David L Erickson, Eric Brown, and Jianghong Meng
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Medicine ,Science - Abstract
We sequenced 25 isolates of phenotypically multidrug-resistant Salmonella Indiana (n = 11), Typhimurium (n = 8), and Enteritidis (n = 6) using both MinION long-read [SQK-LSK109 and flow cell (R9.4.1)] and MiSeq short-read (Nextera XT and MiSeq Reagent Kit v2) sequencing technologies to determine the advantages of each approach in terms of the characteristics of genome structure, antimicrobial resistance (AMR), virulence potential, whole-genome phylogeny, and pan-genome. The MinION reads were base-called in real-time using MinKnow 3.4.8 integrated with Guppy 3.0.7. The long-read-only assembly, Illumina-only assembly, and hybrid assembly pipelines of Unicycler 0.4.8 were used to generate the MinION, MiSeq, and hybrid assemblies, respectively. The MinION assemblies were highly contiguous compared to the MiSeq assemblies but lacked accuracy, a deficiency that was mitigated by adding the MiSeq short reads through the Unicycler hybrid assembly which corrected erroneous single nucleotide polymorphisms (SNPs). The MinION assemblies provided similar predictions of AMR and virulence potential compared to the MiSeq and hybrid assemblies, although they produced more total false negatives of AMR genotypes, primarily due to failure in identifying tetracycline resistance genes in 11 of the 19 MinION assemblies of tetracycline-resistant isolates. The MinION assemblies displayed a large genetic distance from their corresponding MiSeq and hybrid assemblies on the whole-genome phylogenetic tree, indicating that the lower read accuracy of MinION sequencing caused incorrect clustering. The pan-genome of the MinION assemblies contained significantly more accessory genes and less core genes compared to the MiSeq and hybrid assemblies, suggesting that although these assemblies were more contiguous, their sequencing errors reduced accurate genome annotations. Our research demonstrates that MinION sequencing by itself provides an efficient assessment of the genome structure, antimicrobial resistance, and virulence potential of Salmonella; however, it is not sufficient for whole-genome phylogenetic and pan-genome analyses. MinION in combination with MiSeq facilitated the most accurate genomic analyses.
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- 2020
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7. Fragility functions for corroded reinforced concrete columns
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Dai, Kuang-Yu, Yu, Xiao-Hui, Lu, Da-Gang, and Qian, Kai
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- 2024
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8. Heme oxygenase-1 plays a pro-life role in experimental brain stem death via nitric oxide synthase I/protein kinase G signaling at rostral ventrolateral medulla
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Dai Kuang-Yu, Chan Samuel HH, and Chang Alice YW
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Medicine - Abstract
Abstract Background Despite its clinical importance, a dearth of information exists on the cellular and molecular mechanisms that underpin brain stem death. A suitable neural substrate for mechanistic delineation on brain stem death resides in the rostral ventrolateral medulla (RVLM) because it is the origin of a life-and-death signal that sequentially increases (pro-life) and decreases (pro-death) to reflect the advancing central cardiovascular regulatory dysfunction during the progression towards brain stem death in critically ill patients. The present study evaluated the hypothesis that heme oxygnase-1 (HO-1) may play a pro-life role as an interposing signal between hypoxia-inducible factor-1 (HIF-1) and nitric oxide synthase I (NOS I)/protein kinase G (PKG) cascade in RVLM, which sustains central cardiovascular regulatory functions during brain stem death. Methods We performed cardiovascular, pharmacological, biochemical and confocal microscopy experiments in conjunction with an experimental model of brain stem death that employed microinjection of the organophosphate insecticide mevinphos (Mev; 10 nmol) bilaterally into RVLM of adult male Sprague-Dawley rats. Results Western blot analysis coupled with laser scanning confocal microscopy revealed that augmented HO-1 expression that was confined to the cytoplasm of RVLM neurons occurred preferentially during the pro-life phase of experimental brain stem death and was antagonized by immunoneutralization of HIF-1α or HIF-1β in RVLM. On the other hand, the cytoplasmic presence of HO-2 in RVLM neurons manifested insignificant changes during both phases. Furthermore, immunoneutralization of HO-1 or knockdown of ho-1 gene in RVLM blunted the augmented life-and-death signals exhibited during the pro-life phase. Those pretreatments also blocked the upregulated pro-life NOS I/PKG signaling without affecting the pro-death NOS II/peroxynitrite cascade in RVLM. Conclusions We conclude that transcriptional upregulation of HO-1 on activation by HIF-1 in RVLM plays a preferential pro-life role by sustaining central cardiovascular regulatory functions during brain stem death via upregulation of NOS I/PKG signaling pathway. Our results further showed that the pro-dead NOS II/peroxynitrite cascade in RVLM is not included in this repertoire of cellular events.
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- 2010
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9. Cyclic behavior of RC beams under artificial climate rapid freeze-thaw environment: A further research
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Wang, Jun-Yan, Rong, Xian-Liang, Zheng, Shan-Suo, Zhang, Yi-Xin, Dai, Kuang-Yu, Dong, Li-guo, and Wang, Zi-Sheng
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- 2022
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10. Seismic performance of reinforced concrete beams under freeze-thaw cycles
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Rong, Xian-Liang, Zhang, Yi-Xin, Zheng, Shan-Suo, Wang, Jun-Yan, Dong, Li-Guo, and Dai, Kuang-Yu
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- 2022
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11. Deformation capacity of FRP retrofitted reinforced concrete columns with corroded reinforcing bars
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Dai, Kuang-Yu, Yu, Xiao-Hui, Qian, Kai, and Wang, Dai-Yu
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- 2022
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12. Experimental investigation on the seismic performance of corroded reinforced concrete columns designed with low and high axial load ratios
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Dai, Kuang-Yu, Lu, Da-Gang, and Yu, Xiao-Hui
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- 2021
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13. Experimental investigation on seismic behavior of corroded RC columns under artificial climate environment and electrochemical chloride extraction: A comparative study
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Dai, Kuang-Yu, Liu, Chang, Lu, Da-Gang, and Yu, Xiao-Hui
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- 2020
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14. Phenomenological hysteretic model for corroded RC columns
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Dai, Kuang-Yu, Yu, Xiao-Hui, and Lu, Da-Gang
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- 2020
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15. Fragility functions for corroded reinforced concrete columns
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Dai, Kuang-Yu, primary, Yu, Xiao-Hui, additional, Lu, Da-Gang, additional, and Qian, Kai, additional
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- 2023
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16. Seismic behavior of frost-damaged squat RC shear walls under artificial climate environment: a further experimental research
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Rong, Xian-Liang, Zheng, Shan-Suo, Zhang, Yi-Xin, Dong, Li-Guo, Liu, Huan, and Dai, Kuang-Yu
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- 2020
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17. Development of Loop-Mediated Isothermal Amplification Rapid Diagnostic Assays for the Detection of
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Aurore C, Poirier, Dai, Kuang, Bianca S, Siedler, Khushboo, Borah, Jai W, Mehat, Jialin, Liu, Cui, Tai, Xiaoli, Wang, Arnoud H M, van Vliet, Wei, Ma, David R, Jenkins, John, Clark, Roberto M, La Ragione, Jieming, Qu, and Johnjoe, McFadden
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- 2021
18. Variability in corrosion damage models and its effect on seismic collapse fragility of aging reinforced concrete frames
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Yu, Xiao-Hui, primary, Dai, Kuang-Yu, additional, and Li, Yu-Shi, additional
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- 2021
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19. Neuroinflammation and Microglial Activation at Rostral Ventrolateral Medulla Underpin Cadmium-Induced Cardiovascular Dysregulation in Rats
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Tsai, Ching-Yi, primary, Fang, Chi, additional, Wu, Jacqueline CC, additional, Wu, Chiung-Ju, additional, Dai, Kuang-Yu, additional, and Chen, Shu-Mi, additional
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- 2021
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20. Increase in Ceftriaxone Resistance and Widespread Extended-Spectrum β-Lactamases Genes Among Salmonella enterica from Human and Nonhuman Sources
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Xiaowei Yang, Xuebin Xu, Jianghong Meng, Xudong Su, Jianmin Zhang, Weimin Shi, Dai Kuang, and Xianming Shi
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0301 basic medicine ,China ,Salmonella ,Meat ,Nalidixic acid ,Swine ,medicine.medical_treatment ,Salmonella enteritidis ,030106 microbiology ,Microbial Sensitivity Tests ,Drug resistance ,Integron ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,Microbiology ,Poultry ,beta-Lactamases ,Integrons ,03 medical and health sciences ,Antibiotic resistance ,Rivers ,Drug Resistance, Multiple, Bacterial ,medicine ,Animals ,Humans ,biology ,Ceftriaxone ,Salmonella enterica ,biology.organism_classification ,Anti-Bacterial Agents ,030104 developmental biology ,Food Microbiology ,Beta-lactamase ,biology.protein ,Animal Science and Zoology ,Food Science ,medicine.drug - Abstract
Salmonella producing β-lactamases has spread rapidly worldwide and poses a serious threat to human and animal health. In this study, we characterized 220 ceftriaxone (CRO)-resistant isolates identified among 3153 Salmonella from humans, animals, food, and water collected in Shanghai, China. They were assessed for antimicrobial susceptibility, phenotypic identification of extended-spectrum β-lactamases (ESBLs), and β-lactamase genes and integrons. CRO resistance in Salmonella increased from 5.0% in 2011 to 8.4% in 2013. Salmonella Enteritidis (45.5%), Salmonella Typhimurium (20.9%) from humans, and Salmonella Indiana (14.5%) from poultry represented the majority of the CRO-resistant isolates. Many isolates were also resistant to other antimicrobials, including nalidixic acid (84.5%), sulfisoxazole (70.5%), and tetracycline (61.8%). Resistance to ciprofloxacin was also found in 33.6% of the isolates. Most isolates (98.2%) were confirmed as ESBL producers. Resistance genes such as blaCTX-M, blaTEM, and blaOXA were detected in 207 (94.1%), 99 (45%), and 53 (24.1%) isolates, respectively. Three types of integron I and one type of integron II were identified in 13 (5.9%) and 2 (0.9%) isolates, respectively. The integrons encompassed 10 different genes: dfrA1/12/17/25, aadA1/2/5, sat2, orfF, and ybeA. Our study underscores concern for increasing CRO resistance, and highlights the widespread ESBL genes in Salmonella enterica.
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- 2018
21. Start-ups by academics with a migration background (in Germany)
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Dai, Kuang
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jel:M ,300 Sozialwissenschaften ,ddc:300 ,Wirtschaftswissenschaften - Abstract
Die vorliegende Arbeit befasst sich mit Gründungen durch Akademikerinnen und Akademiker mit Migrationshintergrund. Dabei wurden vor allem der Bezug dieser Gründungen zu der Umwelt – dem Gründerökosystem –, in der sie stattfinden, sowie ihre gegenseitigen Wechselwirkungen untersucht. Der Forschungsgegenstand ist die Schnittstelle aus den Bereichen Gründungen, Migrantentum und Hochqualifikation. Der Fokus auf die sehr spezifische Zielgruppe Gründungen durch Akademikerinnen und Akademiker mit Migrationshintergrund füllt eine wichtige Lücke in der bisherigen Forschung. Methodisch gesehen bedient sich diese Arbeit eines theoretischen Bezugsrahmens. Dieser besteht aus der neoinstitutionalistischen Organisationstheorie (Meyer & Rowan 1977), dem Ressourcenabhängigkeitsansatz (Pfeffer & Salancik 1978) sowie dem sechs-dimensionalen Modell des Gründerökosystems (Isenberg 2011). Gründungen durch Akademikerinnen und Akademiker mit Migrationshintergrund müssen ihre interne Ausgestaltung an die Anforderung der institutionellen Umwelt anpassen, um die notwendige Legitimität zu sichern. Dadurch können bei unterschiedlichen Gründungen isomorphe Organisationsstrukturen entstehen. Darüber hinaus können akademische Gründende mit Migrationshintergrund durch interorganisatorische Aktivitäten den Zugang zu nicht-substituierbaren Ressourcen für die Unternehmensgründung bzw. Geschäftsentwicklung ermöglichen bzw. erleichtern. Daher ist die Kombination beider Theorien und des Erklärungsansatzes ein effektives und passendes Analysetool für die vorliegende Forschungsarbeit und schafft sowohl auf Mikro- als auch auf Makroebene für die Leserinnen und Leser ein vollständiges Gesamtbild. Die vorliegende Arbeit beinhaltet nicht nur Daten aus Sekundärquellen und bereits vorhandenen quantitativen Studien im deskriptiven Teil, sondern auch direkte Informationen durch eigene qualitative Untersuchung im empirischen Teil. Dafür wurden insgesamt 23 semistrukturierte Experteninterviews durchgeführt. Durch die Inhaltsanalyse nach Mayring (2014) wurden mehrere Kategorien herausgefiltert; dazu zählen bspw. umweltbezogene Einflussfaktoren auf Legitimität sowie nicht-substituierbare Ressourcen für Gründungen durch Akademikerinnen und Akademiker. Darüber hinaus wurden durch die Empirie einige Hypothesen für weitere quantitative Forschungen in der Zukunft aufgestellt und konkrete Handlungsempfehlungen für die Praxis gegeben., The present paper deals with start-ups by academics with a migration background (in Germany). Above all, the relation of these start-ups to the environment – the entrepreneurial ecosystem – in which they take place, as well as their mutual interactions were examined. The subject of research is the interface between the areas of start-ups, migrants and high qualification. The focus on the very specific target group start-ups by academics with a migration background fills an important gap in previous research. Regarding to the methodological approach, this paper uses a theoretical frame which consists of the theory of neo-institutionalism (Meyer & Rowan 1977), the resource dependence theory (Pfeffer & Salancik 1978) and the six domains model of an entrepreneurship ecosystem (Isenberg 2011). Start-ups by academics with a migration background must adapt their internal structure to the requirements of the institutional environment in order to ensure the necessary legitimacy. This can result in isomorphic organizational structures in different start-ups. In addition, academic founders with a migration background can use interorganizational activities to enable or facilitate access to non-substitutable resources for setting up a company or business development. Therefore, the combination of both theories and the explanatory approach is an effective and suitable analysis tool for the present research work and creates a complete picture for the reader at both the micro and macro level. The present paper contains not only data from secondary sources and already existing quantitative studies in the descriptive part, but also direct information through own qualitative research in the empirical part. A total of 23 semi-structured expert interviews were carried out for this purpose. The content analysis according to Mayring (2014) filtered out several categories; these include, for example, environmental factors influencing legitimacy and non-substitutable resources for start-ups by academics. In addition, some hypotheses for further quantitative research in the future were set up through empirical research and concrete recommendations for action were also given in this paper.
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- 2021
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22. Neuroinflammation and Microglial Activation at Rostral Ventrolateral Medulla Underpin Cadmium-Induced Cardiovascular Dysregulation in Rats
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Tsai,Ching-Yi, Fang,Chi, Wu,Jacqueline CC, Wu,Chiung-Ju, Dai,Kuang-Yu, Chen,Shu-Mi, Tsai,Ching-Yi, Fang,Chi, Wu,Jacqueline CC, Wu,Chiung-Ju, Dai,Kuang-Yu, and Chen,Shu-Mi
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Ching-Yi Tsai,1 Chi Fang,1 Jacqueline CC Wu,1 Chiung-Ju Wu,1 Kuang-Yu Dai,1 Shu-Mi Chen2,3 1Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan; 2Pharmacology and Toxicology, School of Medicine, Tzu Chi University, Hualien, Taiwan; 3Department of Pharmacy, Lotung Poh-Ai Hospital, Yilan, TaiwanCorrespondence: Ching-Yi TsaiInstitute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, 123 Dapi Rd, Kaohsiung 83301, TaiwanTel +886-7-7317123 ext.8598Email cytsai@cgmh.org.twPurpose: Cadmium is a heavy metal and environmental toxicant known to act on the central cardiovascular regulatory mechanisms, and one of its brain targets is the rostral ventrolateral medulla (RVLM), a brainstem site that maintains blood pressure and sympathetic vasomotor tone. The present study assessed the hypothesis that cadmium elicits cardiovascular dysregulation by inducing neuroinflammation and microglial activation, two potential cellular mechanisms, in RVLM.Methods: Adult male SpragueâDawley rats were used for measuring cardiovascular responses after intravenous administration of cadmium. We further conducted real-time PCR, immunofluorescence staining, in situ determination of mitochondrial superoxide, hematoxylin and eosin staining, and enzyme-linked immunosorbent assay (ELISA) to identify cytokine and chemokine mRNA expression, microglia activation, superoxide production, and necrotic and apoptotic cell death in RVLM.Results: We found animals maintained under propofol anesthesia, intravenous administration of cadmium acetate (4 mg/kg) resulted in an increase, followed by a rebound and a secondary decrease in spontaneous baroreflex-mediated sympathetic vasomotor tone, a progressive reduction in mean arterial pressure and heart rate, alongside augmentation of pro-inflammatory cytokine and chemokine in RVLM. All those cardiovascular and neuroinflammatory events were reversed by pretreatment with an anti
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- 2021
23. Emerging high-level ciprofloxacin resistance and molecular basis of resistance in Salmonella enterica from humans, food and animals
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Sheng Chen, Jianmin Zhang, Xudong Su, Weimin Shi, Xiaowei Yang, Dai Kuang, Xianming Shi, Jianghong Meng, and Xuebin Xu
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DNA Topoisomerase IV ,0301 basic medicine ,China ,Salmonella ,Meat ,Swine ,030106 microbiology ,Microbial Sensitivity Tests ,Drug resistance ,Serogroup ,medicine.disease_cause ,Microbiology ,Foodborne Diseases ,03 medical and health sciences ,Antibiotic resistance ,Ciprofloxacin ,Drug Resistance, Multiple, Bacterial ,Pulsed-field gel electrophoresis ,medicine ,Animals ,Humans ,biology ,Molecular epidemiology ,Salmonella enterica ,General Medicine ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,Anti-Bacterial Agents ,Multiple drug resistance ,030104 developmental biology ,DNA Gyrase ,Salmonella Infections ,Chickens ,Plasmids ,Food Science ,medicine.drug - Abstract
Disease caused by nontyphoidal serotypes of Salmonella enterica is the leading cause of foodborne illness worldwide. Many serotypes have also developed resistance to antimicrobials commonly used for the treatment of salmonellosis. Here we analyze 179 ciprofloxacin-resistant isolates identified among 3680 Salmonella isolated from humans, food, animals, and water collected in Shanghai, China. They were assessed for antimicrobial susceptibility, plasmid-mediated quinolone resistance (PMQR) determinants, and mutations in quinolone resistance determination regions (QRDRs); genetic relatedness was examined using PFGE. Ciprofloxacin resistance in Salmonella increased from 2.3% in 2006 to 5.9% in 2012. Multidrug resistance was common, and most carried mutations in QRDR (97.2%) and PMQR determinants (71.5%). Mutations frequently included changes in gyrA: Ser83Phe (53.6%) and Asp87Asn (35.8%), and in parC: Thr57Ser (53.1%) and Ser80Arg (44.1%). Mutations in parC and parE without changes in gyrA were identified in S. Derby and most S. Thompson. Among PMQR determinants, aac(6')-Ib-cr (62.0%) and oqxA/oqxB (33.5%/33.0%) were most common, and conferred resistance without target mutations in five S. Typhimurium isolates. PFGE analysis revealed that S. Typhimurium, isolated from pork and aquatic products, and S. Indiana, isolated from chicken, were highly similar to isolates from humans, suggesting these products be the major source of ciprofloxacin-resistant infections. Our findings highlight the important role QRDRs and PMQR play in ciprofloxacin resistance of Salmonella, and reveal the potential sources of the pathogen associated with human infections.
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- 2018
24. Redox-active DJ-1 sustains brainstem cardiovascular regulation via maintenance of mitochondrial function during mevinphos intoxication
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Tsai, Ching-Yi, primary, Wu, Chiung-Ju, additional, Wu, Jacqueline C.C., additional, Fang, Chi, additional, Huang, Ya-Hui, additional, and Dai, Kuang-Yu, additional
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- 2020
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25. Molecular characterization and antimicrobial susceptibility of Listeria monocytogenes isolated from foods and humans
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Jianmin Zhang, Xudong Su, Yong Li, Xianming Shi, Xiaowei Yang, Jianghong Meng, Xuebin Xu, Haijian Pan, Weimin Shi, and Dai Kuang
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0301 basic medicine ,biology ,Tetracycline ,030106 microbiology ,Virulence ,biology.organism_classification ,medicine.disease_cause ,Subtyping ,Microbiology ,03 medical and health sciences ,Listeria monocytogenes ,Listeria ,medicine ,Pulsed-field gel electrophoresis ,Typing ,Pathogen ,Food Science ,Biotechnology ,medicine.drug - Abstract
A total of 120 Listeria monocytog enes isolates (107 from foods and 13 from humans) in Shanghai, China, were characterized by serogroup typing and virulence genes detection with PCR, antimicrobial susceptibility testing, and molecular subtyping using pulsed-field Gel Electrophoresis (PFGE). Isolates belonged to three L. monocytogenes serogroups, 1/2c, 3c (n = 47, 39.1%) was the most prevalent, followed by 1/2a, 3a (n = 44, 36.7%) and 1/2b, 3b, 7 (n = 29, 24.2%). Although the isolates were all susceptible to most antibiotics tested, 13 isolates were resistant to ceftriaxone and seven to tetracycline. None of the isolates were resistant to multiple antibiotics. The tet (M) genes were detected among tetracycline-resistant isolates. The isolates all harbored virulence genes hly , prfA , plcA , plcB , inlA , inlB , inlI ; 116 isolates (96.7%) were positive for inlC ; 78 (65.0%) for inlG ; 119 (99.2%) for inlJ ; 8 (6.67%) for llsX . A total of 74 distinct patterns were generated for the 119 isolates tested using Apa I and Asc I with Pulsed Field Gel Electrophoresis (PFGE). Three clinical isolates shared the same PFGE patterns with retail meet (chicken, duck, and beef) isolates. These findings indicated that food of animal origin likely serve as a major vehicle in transmitting human listeriosis in Shanghai. Active surveillance for L. monocytogenes is needed for better understanding the epidemiology of the pathogen, and for effective control and prevention of human listeriosis.
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- 2016
26. Characterization of internalin genes in Listeria monocytogenes from food and humans, and their association with the invasion of Caco-2 cells
- Author
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Haijian Pan, Xuebin Xu, Guojie Cao, Xiaowei Yang, Jianmin Zhang, Jianghong Meng, Xianming Shi, Dao-Feng Zhang, Dai Kuang, and Xudong Su
- Subjects
inlA ,0301 basic medicine ,Serotype ,L. monocytogenes ,030106 microbiology ,Virulence ,Single-nucleotide polymorphism ,Biology ,medicine.disease_cause ,Microbiology ,Internalins ,03 medical and health sciences ,Invasion ,Listeria monocytogenes ,Virology ,PMSC mutation ,medicine ,Internalin ,lcsh:RC799-869 ,Gene ,Mutation ,Gastroenterology ,bacterial infections and mycoses ,030104 developmental biology ,Infectious Diseases ,Parasitology ,lcsh:Diseases of the digestive system. Gastroenterology - Abstract
Background Internalins are surface proteins that are utilized by Listeria monocytogenes to facilitate its invasion into human intestinal epithelial cells. The expression of a full-length InlA is one of essential virulence factors for L. monocytogenes to cross the intestinal barrier in order to invade epithelial cells. Results In this study, the gene sequences of inlA in 120 L. monocytogenes isolates from food (n = 107) and humans (n = 13) were analyzed. Premature stop codon (PMSC) mutations in inlA were identified in 51 isolates (50 from food and 1 from human). Six mutation types of PMSCs were identified. Among the 51 isolates with PMSCs in inlA, there were 44 serogroup 1/2c, 3c isolates from food, of which seven belonged to serogroups 1/2a, 3a. A total of 153,382 SNPs in 2247 core genes from 42 genomes were identified and used to construct a phylogenetic tree. Serotype 1/2c isolates with inlA PMSC mutations were grouped together. Cell culture studies on 21 isolates showed that the invasion to Caco-2 cells was significantly reduced among isolates with inlA PMSC mutations compared to those without PMSC mutations (P
- Published
- 2019
27. Transcriptional up-regulation of nitric oxide synthase II by nuclear factor-κB at rostral ventrolateral medulla in a rat mevinphos intoxication model of brain stem death
- Author
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Chan, Julie Y. H., Wu, Carol H. Y., Tsai, Ching-Yi, Cheng, Hsiao-Lei, Dai, Kuang-Yu, Chan, Samuel H. H., and Chang, Alice Y. W.
- Published
- 2007
28. Heat shock protein 60 in rostral ventrolateral medulla reduces cardiovascular fatality during endotoxaemia in the rat
- Author
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Chang, Alice Y. W., Chan, Julie Y. H., Chou, Jimmy L. J., Li, Faith C. H., Dai, Kuang-Yu, and Chan, Samuel H. H.
- Published
- 2006
29. Molecular Characterization, Antimicrobial Resistance and Caco-2 Cell Invasion Potential of Campylobacter jejuni/coli from Young Children with Diarrhea
- Author
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Xiaowei Yang, Xuebin Xu, Xudong Su, Haijian Pan, Zheng Huang, Yanling Ge, Hao Xu, Dai Kuang, Jianghong Meng, Jianmin Zhang, and Xianming Shi
- Subjects
Adult ,Diarrhea ,Male ,0301 basic medicine ,Microbiology (medical) ,Adolescent ,Nalidixic acid ,Virulence Factors ,030106 microbiology ,Erythromycin ,Microbial Sensitivity Tests ,medicine.disease_cause ,Campylobacter jejuni ,Bacterial Adhesion ,Microbiology ,Young Adult ,03 medical and health sciences ,Antibiotic resistance ,Ampicillin ,Campylobacter Infections ,Drug Resistance, Bacterial ,medicine ,Humans ,Child ,Virulence ,biology ,Campylobacter ,Infant, Newborn ,Genetic Variation ,Infant ,Middle Aged ,biology.organism_classification ,Anti-Bacterial Agents ,Ciprofloxacin ,030104 developmental biology ,Infectious Diseases ,Campylobacter coli ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Female ,Caco-2 Cells ,Multilocus Sequence Typing ,medicine.drug - Abstract
BACKGROUND Campylobacter is a major cause of bacterial gastroenteritis worldwide. Young children represent a particular age group affected by Campylobacter infection because of their limited diets and weak immune systems. METHODS In this study, a total of 110 Campylobacter (80 Campylobacter jejuni and 30 Campylobacter coli) isolated from children younger than 5 years of age with diarrhea in Shanghai, China in 2011 were examined for their genetic relationship and antimicrobial susceptibility. The presence of virulence genes and its association with invasion potential in Caco-2 cell were also determined. RESULTS Multilocus sequence typing revealed 62 sequence types (STs) under 14 clonal complexes from C. jejuni and 15 STs under 2 clonal complexes from C. coli. High resistance rates among the 110 isolates were observed to nalidixic acid (88.2%), ciprofloxacin (87.3%) and tetracycline (87.3%), followed by ampicillin (30.9%), gentamicin (28.2%), clindamycin (21.8%), erythromycin (21.8%) and chloramphenicol (8.2%). Compared with that of C. jejuni (32.5%), a larger proportion of C. coli (83.3%) were resistant to multiple antimicrobials, including 16 isolates of ST-828 complex resistant to 6 antimicrobials: ciprofloxacin, clindamycin, erythromycin, gentamicin, nalidixic acid and tetracycline. Furthermore, 57 Campylobacter isolates were selected based on their distinct STs and the presence of virulence genes to determine their abilities to adhere to and invade Caco-2 cells. The level of invasion varied widely among isolates and had relatively weak correlation with the genotype data. CONCLUSION Our findings provided baseline data on Campylobacter among young children. Active surveillance of Campylobacter is needed to better understand the epidemiology and antimicrobial resistance trends of this significant pathogen to help control and protect young children from such infections.
- Published
- 2016
30. Antimicrobial Resistance and Molecular Typing of Salmonella Stanley Isolated from Humans, Foods, and Environment
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Xuebin Xu, Qi Chen, Xiaowei Yang, Jing Zhang, Weimin Shi, Junqing Shen, Dai Kuang, Xianming Shi, Jianghong Meng, Jianmin Zhang, and Haijian Pan
- Subjects
DNA, Bacterial ,Diarrhea ,Serotype ,China ,Disease reservoir ,Nalidixic acid ,Sulfafurazole ,Microbial Sensitivity Tests ,Drug resistance ,Wastewater ,Biology ,Applied Microbiology and Biotechnology ,Microbiology ,Foodborne Diseases ,Antibiotic resistance ,Rivers ,Salmonella ,Drug Resistance, Bacterial ,medicine ,Pulsed-field gel electrophoresis ,Humans ,Disease Reservoirs ,biology.organism_classification ,Electrophoresis, Gel, Pulsed-Field ,Molecular Typing ,Salmonella enterica ,Salmonella Infections ,Food Microbiology ,Animal Science and Zoology ,Water Microbiology ,Food Science ,medicine.drug - Abstract
Salmonella enterica serovar Stanley is an important serovar that has been increasingly identified in human salmonellosis. The present study aimed to investigate the antimicrobial resistance and molecular typing of 88 Salmonella Stanley strains isolated from humans (diarrhea patients, n = 64; and healthy carrier, n = 1), foods (aquatic products, n = 16; vegetable, n = 1; and pork, n = 1), and environment (waste water, n = 2; and river water, n = 3) in Shanghai, China from 2006 to 2012. Nearly half of the strains were resistant to sulfafurazole (43/88, 48.9%), and many were resistant to streptomycin (35/88, 39.8%), tetracycline (22/88, 25%), and nalidixic acid (19/88, 21.6%). Approximately a quarter of the strains (24/88, 27.3%) were resistant to more than three antimicrobials, and five had ACSSuT resistance type. Six clusters (A-F) were identified by pulsed-field gel electrophoresis (PFGE) with 80% similarity. Interestingly, strains in the same cluster identified by PFGE possessed similar antibiotic resistance patterns. PFGE typing also indicated that aquatic products might serve as a transmission reservoir for Salmonella Stanley infections in humans.
- Published
- 2015
31. Genomic analyses of multidrug-resistant Salmonella Indiana, Typhimurium, and Enteritidis isolates using MinION and MiSeq sequencing technologies
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Narjol Gonzalez-Escalona, Zhao Chen, Xuebin Xu, Eric W. Brown, Jianghong Meng, Dai Kuang, and David L. Erickson
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Salmonella typhimurium ,Bacterial Diseases ,Pathology and Laboratory Medicine ,Genome ,Salmonella ,Antibiotics ,Drug Resistance, Multiple, Bacterial ,Genotype ,Medicine and Health Sciences ,Genome Sequencing ,Phylogeny ,Data Management ,0303 health sciences ,Multidisciplinary ,Virulence ,Phylogenetic tree ,Antimicrobials ,Salmonella enterica ,Drugs ,Phylogenetic Analysis ,Genomics ,Anti-Bacterial Agents ,Bacterial Pathogens ,Phylogenetics ,Phenotype ,Infectious Diseases ,Medical Microbiology ,Tetracyclines ,Medicine ,Pathogens ,Plasmids ,Research Article ,Computer and Information Sciences ,Science ,Microbial Sensitivity Tests ,Computational biology ,Biology ,Research and Analysis Methods ,Microbiology ,DNA sequencing ,03 medical and health sciences ,Enterobacteriaceae ,Microbial Control ,Genetics ,Point Mutation ,Evolutionary Systematics ,Molecular Biology Techniques ,Sequencing Techniques ,Microbial Pathogens ,Molecular Biology ,Gene ,Taxonomy ,030304 developmental biology ,Pharmacology ,Evolutionary Biology ,Whole Genome Sequencing ,Bacteria ,030306 microbiology ,Organisms ,Biology and Life Sciences ,Computational Biology ,Genome Analysis ,Genomic Libraries ,Salmonella enteritidis ,Minion ,Mutation ,Antimicrobial Resistance ,Genome, Bacterial - Abstract
We sequenced 25 isolates of phenotypically multidrug-resistant Salmonella Indiana (n = 11), Typhimurium (n = 8), and Enteritidis (n = 6) using both MinION long-read [SQK-LSK109 and flow cell (R9.4.1)] and MiSeq short-read (Nextera XT and MiSeq Reagent Kit v2) sequencing technologies to determine the advantages of each approach in terms of the characteristics of genome structure, antimicrobial resistance (AMR), virulence potential, whole-genome phylogeny, and pan-genome. The MinION reads were base-called in real-time using MinKnow 3.4.8 integrated with Guppy 3.0.7. The long-read-only assembly, Illumina-only assembly, and hybrid assembly pipelines of Unicycler 0.4.8 were used to generate the MinION, MiSeq, and hybrid assemblies, respectively. The MinION assemblies were highly contiguous compared to the MiSeq assemblies but lacked accuracy, a deficiency that was mitigated by adding the MiSeq short reads through the Unicycler hybrid assembly which corrected erroneous single nucleotide polymorphisms (SNPs). The MinION assemblies provided similar predictions of AMR and virulence potential compared to the MiSeq and hybrid assemblies, although they produced more total false negatives of AMR genotypes, primarily due to failure in identifying tetracycline resistance genes in 11 of the 19 MinION assemblies of tetracycline-resistant isolates. The MinION assemblies displayed a large genetic distance from their corresponding MiSeq and hybrid assemblies on the whole-genome phylogenetic tree, indicating that the lower read accuracy of MinION sequencing caused incorrect clustering. The pan-genome of the MinION assemblies contained significantly more accessory genes and less core genes compared to the MiSeq and hybrid assemblies, suggesting that although these assemblies were more contiguous, their sequencing errors reduced accurate genome annotations. Our research demonstrates that MinION sequencing by itself provides an efficient assessment of the genome structure, antimicrobial resistance, and virulence potential of Salmonella; however, it is not sufficient for whole-genome phylogenetic and pan-genome analyses. MinION in combination with MiSeq facilitated the most accurate genomic analyses.
- Published
- 2020
32. Antimicrobial resistance, virulence genes and molecular subtypes of S. Enteritidis isolated from children in Shanghai
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Li Xu, Yue Liu, Xiujuan Zhou, Xuebin Xu, Dai Kuang, Xianming Shi, and Karl R. Matthews
- Subjects
Salmonella ,Sulfafurazole ,Salmonella enteritidis ,Virulence ,General Medicine ,Biology ,medicine.disease_cause ,Microbiology ,Multiple drug resistance ,Infectious Diseases ,Antibiotic resistance ,Virology ,Ampicillin ,Pulsed-field gel electrophoresis ,medicine ,Parasitology ,medicine.drug - Abstract
Introduction: Antimicrobial resistance of Salmonella poses a key threat to public health worldwide. Salmonella Enteritidis (S. Enteritidis) (119 isolates) from children under 10 years old with diarrhea in Shanghai from 2010-2012 were characterized for antimicrobial susceptibility, virulence gene profiles and pulsed field gel electrophoresis (PFGE) patterns. Methodology: The minimum inhibitory concentration for the 119 S. Enteritidis isolates was determined using an agar dilution method. The presence of virulence genes was detected by polymerase chain reaction (PCR). All the isolates with antimicrobial resistance were subjected to PFGE analysis. Results: Among these isolates, 71.4% (85) were resistant to sulfafurazole, 59.7% (71) were resistant to ampicillin, 47.1% (56) were resistant to streptomycin, 7.6% (9) were resistant to ceftiofur and 3.4% (4) were resistant to ceftriaxone. Multidrug resistance (MDR) was found in 63.9% (76) of the isolates; 23 resistance profiles were identified. All isolates harbored the ssaQ and sopE virulence genes in the 16 virulence profiles (VPs); VP1 accounted for 70.59% of the 119 isolates. There were 57 PFGE patterns among the 92 isolates tested, mainly grouped into five clusters (A to E). All of the 76 MDR isolates carried multiple virulence genes. Conclusions: Our study provides useful microbiological data for the successful treatment of S. Enteritidis infections in Shanghai. Although broad spectrum antimicrobials may be useful in the treatment of invasive S. Enteritidis infections, clinicians need to be aware of common microbiological traits, because of the high prevalence of MDR.
- Published
- 2017
33. Draft Genome Sequences of Three
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Xudong, Su, Guojie, Cao, Dai, Kuang, Jianmin, Zhang, Yi, Chen, Marc, Allard, Eric, Brown, Xianming, Shi, Jianghong, Meng, and Xuebin, Xu
- Subjects
Prokaryotes - Abstract
Listeria monocytogenes is a foodborne pathogen of global concern because of the high mortality rate among patients. The draft genome sequences of three L. monocytogenes strains isolated from foods are reported here. The availability of these genomes should provide useful information on the genomic diversity of L. monocytogenes isolated from foods in China.
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- 2017
34. Draft Genome Sequences of Three Listeria monocytogenes Isolates from Foods in China
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Dai Kuang, Marc W. Allard, Jianmin Zhang, Jianghong Meng, Yi Chen, Xuebin Xu, Xianming Shi, Xudong Su, Guojie Cao, and Eric W. Brown
- Subjects
0301 basic medicine ,03 medical and health sciences ,030104 developmental biology ,Foodborne pathogen ,Listeria monocytogenes ,030106 microbiology ,Genetics ,medicine ,Biology ,medicine.disease_cause ,Molecular Biology ,Genome ,Microbiology - Abstract
Listeria monocytogenes is a foodborne pathogen of global concern because of the high mortality rate among patients. The draft genome sequences of three L. monocytogenes strains isolated from foods are reported here. The availability of these genomes should provide useful information on the genomic diversity of L. monocytogenes isolated from foods in China.
- Published
- 2017
35. Antimicrobial Susceptibility and Molecular Typing of Salmonella Senftenberg Isolated from Humans and Other Sources in Shanghai, China, 2005 to 2011
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Yulong Ye, Jianmin Zhang, Jianghong Meng, Zeqiang Zhan, Xuebin Xu, Xueming Hu, Jingzhang Lu, Hongxia Zhang, Dai Kuang, and Ming Liao
- Subjects
0301 basic medicine ,Serotype ,Salmonella ,China ,030106 microbiology ,Antimicrobial susceptibility ,Microbial Sensitivity Tests ,Biology ,medicine.disease_cause ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,Anti-Infective Agents ,Salmonella Senftenberg ,Pulsed-field gel electrophoresis ,medicine ,Humans ,030212 general & internal medicine ,Gel electrophoresis ,Zoonosis ,Salmonella enterica ,medicine.disease ,Antimicrobial ,Electrophoresis, Gel, Pulsed-Field ,Molecular Typing ,Food Science - Abstract
Salmonella Senftenberg is an important nontyphoidal Salmonella serovar that causes gastrointestinal disease worldwide. In total, 130 Salmonella Senftenberg strains obtained from humans, food, and the environment in Shanghai, People's Republic of China, were characterized for antimicrobial susceptibility and subjected to molecular typing. Our findings indicated that most (96 of 130, 73.8%) of the strains were susceptible to all 13 antimicrobial compounds tested, whereas only two strains (1.5%) were resistant to two antimicrobial compounds. In total, 56 pulsed-field gel electrophoresis profiles were identified, including four main pulsed-field gel electrophoresis profiles (X2, X3, X4, and X5) that showed 95.7% genetic similarity. Our study revealed that the strains of Salmonella Senftenberg from food and the environment shared a high correlation of genetic similarity with those from humans, highlighting the potential links that exist among the strains recovered from different sources in Shanghai.
- Published
- 2017
36. PTEN/FLJ10540/PI3K/Akt cascade in experimental brain stem death: A newfound role for a classical tumorigenic signaling pathway
- Author
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Tsai, Ching-Yi, primary, Dai, Kuang-Yu, additional, Fang, Chi, additional, Wu, Jacqueline C.C., additional, and Chan, Samuel H.H., additional
- Published
- 2018
- Full Text
- View/download PDF
37. Turtles as a Possible Reservoir of Nontyphoidal Salmonella in Shanghai, China
- Author
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Ming Liao, Xiaowei Yang, Yongbiao Zhang, Jianghong Meng, Jianmin Zhang, Fei Wang, Xuebin Xu, Dai Kuang, John D. Klena, Shuyu Wu, and Huiming Jin
- Subjects
0301 basic medicine ,Serotype ,Salmonella typhimurium ,Salmonella ,Veterinary medicine ,Disease reservoir ,China ,030106 microbiology ,Terrapin ,Microbial Sensitivity Tests ,medicine.disease_cause ,01 natural sciences ,Applied Microbiology and Biotechnology ,Microbiology ,Article ,03 medical and health sciences ,Feces ,Drug Resistance, Bacterial ,medicine ,Food microbiology ,Animals ,Humans ,Serotyping ,Pathogen ,Phylogeny ,Disease Reservoirs ,biology ,010401 analytical chemistry ,biology.organism_classification ,0104 chemical sciences ,Salmonella Food Poisoning ,Electrophoresis, Gel, Pulsed-Field ,Turtles ,Food Microbiology ,Animal Science and Zoology ,Food Science - Abstract
Terrapins and turtles are known to transmit Salmonella to humans. However, little was known about the occurrence of this pathogen in soft-shelled terrapin that is a popular delicacy in Chinese and other East Asian cuisines. We isolated and characterized 82 (24.4%) isolates of Salmonella from 336 fecal samples of soft-shelled terrapins (51 of 172; 29.7%) and pet turtles (31 of 164; 18.9%) in Shanghai. Salmonella Thompson was the most common serotype (17.1%) among others. Many isolates (84.1%) were resistant to multiple antimicrobials (≥3). Molecular analysis of Salmonella Thompson and Salmonella Typhimurium using pulsed-field gel electrophoresis unveiled a close genetic relationship between several human and terrapin isolates. Our results highlight the risk associated with the handling and consumption of turtles and their role in the spread of Salmonella in the human salmonellosis.
- Published
- 2016
38. Antimicrobial susceptibility, virulence gene profiles and molecular subtypes of Salmonella Newport isolated from humans and other sources
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Ming Liao, Xianmin Shi, Huiming Jin, Xiaowei Yang, Haijian Pan, Weimin Shi, Jianghong Meng, Xuebin Xu, Xudong Su, Jianmin Zhang, and Dai Kuang
- Subjects
Microbiology (medical) ,Serotype ,DNA, Bacterial ,Salmonella ,Nalidixic acid ,Genomic Islands ,Tetracycline ,Virulence ,Microbial Sensitivity Tests ,Biology ,medicine.disease_cause ,Microbiology ,Drug Resistance, Bacterial ,Genetics ,medicine ,Pulsed-field gel electrophoresis ,Humans ,Molecular Biology ,Gene ,Ecology, Evolution, Behavior and Systematics ,Pathogenicity island ,Anti-Bacterial Agents ,Electrophoresis, Gel, Pulsed-Field ,Molecular Typing ,Infectious Diseases ,medicine.drug - Abstract
Salmonella Newport (S. Newport) is a major serotype associated with human salmonellosis. A total of 79 S. Newport recovered from humans and other sources in China were characterized for antimicrobial susceptibility, virulence gene profiles and molecular subtypes using pulsed field gel electrophoresis (PFGE). Approximately 63.3% of the isolates were susceptible to all of 16 antimicrobials tested. Nearly one third of the isolates (31.6%) were resistant to sulfisoxazole, 20.3% to tetracycline and 13.9% to nalidixic acid. Twelve isolates (15.2%) were resistant to three or more antimicrobials. Among 10 virulence genes detected, Salmonella pathogenicity island genes avrA, ssaQ, mgtC, siiD, and sopB and fimbrial gene bcfC were present in most of the isolates (93.7% to 100%). Overall, we observed nine distinct virulence gene profiles, three of which (VP1, VP2 and VP3) were most common (86.1%). A total of 56 PFGE patterns were identified and mainly grouped into seven clusters (A to G) with 80% pattern similarity. Isolates from aquatic product shared a high similarity with those from humans in several clusters, highlighting a potential risk of aquatic product as a source of S. Newport that infect humans. Furthermore, there was a strong association between certain PFGE clusters and virulence gene profiles, suggesting virulence subtyping can be a useful epidemiological tool to discriminate S. Newport isolates.
- Published
- 2015
39. Antimicrobial susceptibility and molecular typing of salmonella agona isolated from humans and other sources
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Xiaowei Yang, Xuebin Xu, Tao Ren, Huiming Jin, Dai Kuang, Yan Tao, Kaijian Luo, Haijian Pan, Jianmin Zhang, Jianghong Meng, and Weimin Shi
- Subjects
Serotype ,Veterinary medicine ,China ,Meat ,Swine ,Salmonella agona ,Drug resistance ,Microbial Sensitivity Tests ,Biology ,Applied Microbiology and Biotechnology ,Microbiology ,Drug Resistance, Bacterial ,Pulsed-field gel electrophoresis ,Animals ,Humans ,food and beverages ,Salmonella enterica ,Antimicrobial ,biology.organism_classification ,Subtyping ,Salmonella Food Poisoning ,Anti-Bacterial Agents ,Electrophoresis, Gel, Pulsed-Field ,Molecular Typing ,Salmonella Infections ,Animal Science and Zoology ,Cattle ,Chickens ,Food Science - Abstract
Salmonella enterica serotype Agona (Salmonella Agona) has been among the top 10 serotypes that cause human diarrheal diseases in China. A total of 95 Salmonella Agona (67 from humans, and 28 from animals, food of animal origins, and environmental sources) recovered in Shanghai, China from 2005 to 2011 were subjected to antimicrobial susceptibility testing and molecular subtyping using pulsed-field gel electrophoresis (PFGE). Approximately 68.4% of the Salmonella Agona isolates were pansusceptible to 15 antimicrobial agents tested, and 4 isolates (4.21%) were resistant to at least 3 antimicrobials. PFGE analysis resulted in 41 unique patterns, of which 4 major PFGE patterns (X3, X4, X5, and X6) were grouped together at 96.1% similarity. Isolates of the four patterns included those from food (pork, beef, and chicken) and humans. Our findings showed that the same clones of Salmonella Agona were recovered from human patients and food, and that food of animal origin was potentially a major vehicle of Salmonella Agona in human salmonellosis in Shanghai.
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- 2014
40. Molecular analysis and antimicrobial susceptibility of enterotoxigenic Escherichia coli from diarrheal patients
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Dai Kuang, Pingping Zhang, Weimin Shi, Jianghong Meng, Xiaowei Yang, Xuebin Xu, Xianming Shi, Jiayin Guo, Haijian Pan, Zheng Huang, Yong Li, Wenting Ju, Jianmin Zhang, and Huiming Jin
- Subjects
Microbiology (medical) ,Adult ,Diarrhea ,Male ,China ,Adolescent ,Genotype ,Virulence Factors ,Virulence ,Biology ,medicine.disease_cause ,Microbiology ,Young Adult ,Enterotoxigenic Escherichia coli ,Pulsed-field gel electrophoresis ,medicine ,Humans ,Child ,Gene ,Escherichia coli Infections ,Aged ,Aged, 80 and over ,Molecular Epidemiology ,Infant, Newborn ,Outbreak ,Infant ,General Medicine ,Middle Aged ,Antimicrobial ,Subtyping ,Anti-Bacterial Agents ,Molecular Typing ,Infectious Diseases ,Child, Preschool ,Multilocus sequence typing ,Female - Abstract
A total of 123 enterotoxigenic Escherichia coli (ETEC) isolates from diarrheal patients from June to December 2012 in Shanghai, China, were examined to determine their genetic relatedness using multilocus sequence typing and pulsed-field gel electrophoresis (PFGE) and for the presence of virulence genes and antimicrobial susceptibility. Twenty-nine sequence types (STs) and 63 PFGE patterns were identified, and results from the 2 subtyping methods correlated well. The 12 isolates of PFGE cluster B all belonged to ST-2332 and were associated with nosocomial neonatal diarrhea. Isolates of a cluster usually had the same set of virulence factors, whereas isolates of different PFGE clusters carried diverse combinations of virulence determinants. Isolates belonging to ST-2332 and ST-182 (n=9) were resistant to at least 6 antimicrobials. Our findings highlighted the need of active surveillance programs for infectious diseases collecting data at both epidemiological and genetic levels that can detect high-risk lineages of pathogens in order to rapidly identify disease outbreaks.
- Published
- 2014
41. Interplay between brain stem angiotensins and monocyte chemoattractant protein-1 as a novel mechanism for pressor response after ischemic stroke
- Author
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Chang, Alice Y.W., primary, Li, Faith C.H., additional, Huang, Chi-Wei, additional, Wu, Julie C.C., additional, Dai, Kuang-Yu, additional, Chen, Chang-Han, additional, Li, Shau-Hsuan, additional, Su, Chia-Hao, additional, and Wu, Re-Wen, additional
- Published
- 2014
- Full Text
- View/download PDF
42. Molecular Characterization, Antimicrobial Resistance and Caco-2 Cell Invasion Potential of Campylobacter jejuni/coli from Young Children with Diarrhea.
- Author
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Haijian Pan, Yanling Ge, Hao Xu, Jianmin Zhang, Dai Kuang, Xiaowei Yang, Xudong Su, Zheng Huang, Xianming Shi, Xuebin Xu, and Jianghong Meng
- Published
- 2016
- Full Text
- View/download PDF
43. Sumoylation of Hypoxia-Inducible Factor-1α Ameliorates Failure of Brain Stem Cardiovascular Regulation in Experimental Brain Death
- Author
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Chan, Julie Y. H., primary, Tsai, Ching-Yi, additional, Wu, Carol H. Y., additional, Li, Faith C. H., additional, Dai, Kuang-Yu, additional, Sun, Enya Y. H., additional, Chan, Samuel H. H., additional, and Chang, Alice Y. W., additional
- Published
- 2011
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44. Heat Shock Protein 60 or 70 Activates Nitric-oxide Synthase (NOS) I- and Inhibits NOS II-associated Signaling and Depresses the Mitochondrial Apoptotic Cascade during Brain Stem Death
- Author
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Chan, Julie Y.H., primary, Cheng, Hsiao-Lei, additional, Chou, Jimmy L.J., additional, Li, Faith C.H., additional, Dai, Kuang-Yu, additional, Chan, Samuel H.H., additional, and Chang, Alice Y.W., additional
- Published
- 2007
- Full Text
- View/download PDF
45. Antimicrobial resistance, virulence genes and molecular subtypes of S. Enteritidis isolated from children in Shanghai.
- Author
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Li Xu, Xiujuan Zhou, Xuebin Xu, Matthews, Karl R., Yue Liu, Dai Kuang, and Xianming Shi
- Subjects
- *
ANTI-infective agents , *MICROBIAL virulence , *FOOD pathogens , *SALMONELLA enterica , *DRUG resistance - Abstract
Introduction: Antimicrobial resistance of Salmonella poses a key threat to public health worldwide. Salmonella Enteritidis (S. Enteritidis) (119 isolates) from children under 10 years old with diarrhea in Shanghai from 2010-2012 were characterized for antimicrobial susceptibility, virulence gene profiles and pulsed field gel electrophoresis (PFGE) patterns. Methodology: The minimum inhibitory concentration for the 119 S. Enteritidis isolates was determined using an agar dilution method. The presence of virulence genes was detected by polymerase chain reaction (PCR). All the isolates with antimicrobial resistance were subjected to PFGE analysis. Results: Among these isolates, 71.4% (85) were resistant to sulfafurazole, 59.7% (71) were resistant to ampicillin, 47.1% (56) were resistant to streptomycin, 7.6% (9) were resistant to ceftiofur and 3.4% (4) were resistant to ceftriaxone. Multidrug resistance (MDR) was found in 63.9% (76) of the isolates; 23 resistance profiles were identified. All isolates harbored the ssaQ and sopE virulence genes in the 16 virulence profiles (VPs); VP1 accounted for 70.59% of the 119 isolates. There were 57 PFGE patterns among the 92 isolates tested, mainly grouped into five clusters (A to E). All of the 76 MDR isolates carried multiple virulence genes. Conclusions: Our study provides useful microbiological data for the successful treatment of S. Enteritidis infections in Shanghai. Although broad spectrum antimicrobials may be useful in the treatment of invasive S. Enteritidis infections, clinicians need to be aware of common microbiological traits, because of the high prevalence of MDR. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
46. Transcriptional up-regulation of nitric oxide synthase II by nuclear factor-kappaB at rostral ventrolateral medulla in a rat mevinphos intoxication model of brain stem death.
- Author
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Chan JY, Wu CH, Tsai CY, Cheng HL, Dai KY, Chan SH, and Chang AY
- Subjects
- Animals, Blood Pressure, Brain Death pathology, Brain Death physiopathology, Cyclic GMP-Dependent Protein Kinases metabolism, Diamines pharmacology, Disease Models, Animal, Ditiocarb pharmacology, Enzyme Induction, Heart Rate, Male, Medulla Oblongata drug effects, Medulla Oblongata enzymology, Medulla Oblongata pathology, Mevinphos, Muscarinic Antagonists pharmacology, NF-kappa B antagonists & inhibitors, NF-kappa B genetics, Nitric Oxide Synthase biosynthesis, Nitric Oxide Synthase Type I, Nitric Oxide Synthase Type II genetics, Pyrrolidines pharmacology, Rats, Rats, Sprague-Dawley, Receptor, Muscarinic M2 antagonists & inhibitors, Receptor, Muscarinic M4 antagonists & inhibitors, Reproducibility of Results, Thiocarbamates pharmacology, Time Factors, Tropicamide pharmacology, Tyrosine analogs & derivatives, Tyrosine metabolism, Brain Death metabolism, Medulla Oblongata metabolism, NF-kappa B metabolism, Nitric Oxide Synthase Type II biosynthesis, Receptor, Muscarinic M2 metabolism, Receptor, Muscarinic M4 metabolism, Transcription, Genetic drug effects
- Abstract
As the origin of a 'life-and-death' signal that reflects central cardiovascular regulatory failure during brain stem death, the rostral ventrolateral medulla (RVLM) is a suitable neural substrate for mechanistic delineation of this vital phenomenon. Using a clinically relevant animal model that employed the organophosphate pesticide mevinphos (Mev) as the experimental insult, we evaluated the hypothesis that transcriptional up-regulation of nitric oxide synthase I or II (NOS I or II) gene expression by nuclear factor-kappaB (NF-kappaB) on activation of muscarinic receptors in the RVLM underlies brain stem death. In Sprague-Dawley rats maintained under propofol anaesthesia, co-microinjection of muscarinic M2R (methoctramine) or M4R (tropicamide), but not M1R (pirenzepine) or M3R (4-diphenylacetoxy-N-dimethylpiperidinium) antagonist significantly reduced the enhanced NOS I-protein kinase G signalling ('pro-life' phase) or augmented NOS II-peroxynitrite cascade ('pro-death' phase) in ventrolateral medulla, blunted the biphasic increase and decrease in baroreceptor reflex-mediated sympathetic vasomotor tone that reflect the transition from life to death, and diminished the elevated DNA binding activity or nucleus-bound translocation of NF-kappaB in RVLM neurons induced by microinjection of Mev into the bilateral RVLM. However, NF-kappaB inhibitors (diethyldithiocarbamate or pyrrolidine dithiocarbamate) or double-stranded kappaB decoy DNA preferentially antagonized the augmented NOS II-peroxynitrite cascade and the associated cardiovascular depression exhibited during the 'pro-death' phase. We conclude that transcriptional up-regulation of NOS II gene expression by activation of NF-kappaB on selective stimulation of muscarinic M2 or M4 subtype receptors in the RVLM underlies the elicited cardiovascular depression during the 'pro-death' phase in our Mev intoxication model of brain stem death.
- Published
- 2007
- Full Text
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